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arXiv · 0711.4524

$T_c$ Dependence of Energy Gap and Asymmetry of Coherence Peaks in NdBa$_2$Cu$_3$O$_{7-δ}$

P. Das·M. R. Koblischka·Th. Wolf·P. Adelmann·U. Hartmann
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Abstract

We report here the results of scanning tunneling spectroscopic experiments performed on hole doped NdBa$_2$Cu$_3$O$_{7-δ}$ single crystals of $T_c$ values of 76 K, 93.5 K and 95.5 K. The energy gaps are observed to be increasing with decreasing $T_c$ values. The coherence peaks are asymmetric with the peaks at the filled states being larger than those at the empty ones. The asymmetry increases with decreasing $T_c$. The observed asymmetry and its $T_c$ dependence can be explained by considering the Mott insulating nature of the material at the undoped state.

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P. Das, M. R. Koblischka, Th. Wolf, P. Adelmann, U. Hartmann. 2008-10-16. $T_c$ Dependence of Energy Gap and Asymmetry of Coherence Peaks in NdBa$_2$Cu$_3$O$_{7-δ}$. https://doi.org/10.1209/0295-5075/84/47004

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